JP2005348804A - Drum type washing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve accuracy in adjusting a balance by preventing undesired movement of laundry in an attempt to reduce an eccentric load by utilizing the movement of a liquid inside a balancer rotating integrally with a drum. <P>SOLUTION: The quantity of moment of inertia is measured when the drum is rotated at a speed of 100 rpm, and the quantity of the load in the moisture-retaining state is detected based on the measurement. In executing the balance adjustment, the speed is temporarily reduced (S23) when the eccentric load caused by the laundry gathered to one side reaches a prescribed point from the state of rotation of the drum (and the balancer) at the speed of 100 rpm (S22), and the speed of rotation for the shift from the deceleration to the acceleration is set the higher as the quantity of load is the larger (S24-S28). The distance from the laundry located on the innermost side in the drum to the rotation shaft is short when the quantity of load is large. However, as the rotational speed at the time of deceleration is high, the reduction of the centrifugal force is controlled small, so that the laundry hardly falls down. Accordingly, the liquid in the balancer can be accurately moved while preventing movement of the laundry at the time of temporary deceleration of rotation of the drum. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a drum-type washing machine, and more particularly to a technique for suppressing or reducing vibrations generated during centrifugal dehydration.

  In a drum-type washing machine, a substantially cylindrical drum having a circumferential surface having a large number of water holes is rotated at a high speed around a horizontal or inclined axis, whereby wet laundry contained in the drum Dewatering is performed by squeezing out and dispersing the water contained in the water. During such centrifugal dewatering, if the laundry is arranged in the circumferential direction on the inner peripheral surface of the drum, and if there is a mass imbalance (ie, eccentric load) around the rotation axis, the rotation speed of the drum is increased. When this occurs, the drum vibrates greatly, and the outer tub that houses the drum vibrates and contacts the inner surface of the outer box or the outer box itself vibrates, causing abnormal noise. For this reason, reducing vibration and noise during centrifugal dehydration is a major problem in drum-type washing machines.

  As one of such vibration suppression techniques during centrifugal dehydration, those described in Patent Documents 1 and 2 and Non-Patent Document 1 are known. In the drum type washing machine described in these documents, a balancer including an annular and hollow balance chamber is provided on both end faces of the drum. In the balance chamber, partition walls are formed radially inward from the outer peripheral wall surface, and the balance chamber is partitioned into a number of partition chambers whose inner peripheral side is open by the partition walls. A predetermined amount of liquid is sealed in the balance chamber, and the liquid enters and exits the partition chamber through the open surface on the inner peripheral side of each partition chamber. When the drum is rotated at such a rotational speed that the centrifugal force acting on the liquid is stored in each compartment and the centrifugal force acting on the liquid is superior to gravity, the liquid in each compartment is held in the compartment, and the balancer Its own eccentric load becomes almost zero. If the rotation speed of the drum is lowered from this state and the liquid stored in some of the compartments is dropped and moved to other compartments, the amount of liquid in each compartment becomes non-uniform, thereby causing the balancer itself. An eccentric load is generated. Even if there is an eccentric load due to the laundry being offset, the eccentric load of the entire drum can be reduced by moving the balancer liquid to a position where it can be offset. Vibration and noise can be suppressed.

  In a drum type washing machine, there is generally a resonance point at which vibration is maximized in a range lower than the rotational speed at which centrifugal dehydration is performed. Therefore, when the drum rotational speed is raised to the dehydrating rotational speed, the resonance point is always passed. Since the balance adjustment using the balancer can be performed at a rotation speed lower than the resonance point, if the eccentric load is reduced by the balance adjustment and the drum rotation speed is increased to the dehydration rotation speed, the resonance point is obtained. The vibration of the outer tub and the outer box can be effectively suppressed even when passing through.

  However, in the balance adjustment technique described above, since the centrifugal force acting on the balancer liquid is reduced by temporarily reducing the rotational speed of the drum, the centrifugal force is reduced when the rotational speed is reduced. As a result, the laundry stuck to the inner peripheral surface of the drum may also fall or be displaced. In such a case, the position and magnitude of the eccentric load caused by the laundry being displaced will change, and even if the balancer liquid can be moved to cancel the original eccentric load, the eccentric load itself If the position or size changes, it becomes impossible to cancel. In addition, if this is repeated, the balance adjustment will take a very long time, and the dehydration time and thus the time required for washing will be greatly prolonged.

JP 2003-220293 A JP 2003-230791 A “Drum-type washer / dryer AWD-B860Z (S) Running cost and other nice functions”, “Realization of low vibration and low noise by digital G-Fall control!”, [Online], Sanyo Electric Co., Ltd. [Heisei Search on May 31, 2016], Internet, <URL: http://www.sanyo-laundry.com/awd/06/main.html>

  The present invention has been made to solve the above problems, and in the drum type washing machine configured as described above, the balance liquid is moved by utilizing the relationship between the centrifugal force and the gravity. The purpose of this invention is to prevent the fluctuation of the eccentric load due to the side of the laundry sometimes, and to make a good balance adjustment.

The present invention made to solve the above problems is a drum-type washing machine that dehydrates the laundry by rotating the drum containing the laundry at high speed around a horizontal axis or an inclined axis.
A load amount detecting means for detecting a load amount in a wet state before the start of dehydration;
In order to generate a load on the drum that counteracts the eccentric load caused by the deviation of the laundry in the drum, the drum is mounted on one or both end surfaces of the drum and formed radially around the drum rotation axis. A balancer having a plurality of liquid storage tanks having openings on the inner peripheral side;
While the drum is rotating at a rotational speed at which the centrifugal force acting on the laundry in the drum is greater than gravity and lower than the resonant rotational speed corresponding to the resonance point, An eccentric load detecting means for detecting an eccentric load caused by the offset, and
From the state where the drum is rotated at such a rotational speed that the centrifugal force acting on the liquid in each liquid storage tank of the balancer is greater than the gravity, the rotational position of the eccentric load detected by the eccentric load detecting means is changed. By decelerating for a short time at the appropriate timing, the liquid in the liquid storage tank located above the rotation is dropped and moved to another liquid storage tank or discarded, thereby changing the eccentric state of the balancer. Balance adjustment control means for adjusting the balance of the entire drum, and a balance adjustment control means for changing a rotation speed for switching from deceleration to acceleration at the time of deceleration according to the load amount by the load amount detection means,
It is characterized by having.

As a specific embodiment, the balancer includes a sealed annular body that is concentrically and integrally rotatable with the drum and has a hollow inside, and a liquid sealed in the annular body, A plurality of partition walls project radially inward from the outer peripheral surface side inside the sealed annular body, communicate with each other on the inner peripheral surface side between adjacent partition walls, and the liquid is formed on the outer peripheral surface side by centrifugal force. Having a plurality of compartments capable of holding the liquid storage tank,
The balance adjustment control means temporarily lowers the rotational speed of the drum and balancer from a state where the centrifugal force acting on the liquid held in the compartment rotates at a rotational speed that overcomes gravity, It can be set as the structure which moves the liquid currently hold | maintained at each compartment to another compartment.

  In the drum type washing machine according to the present invention, since the balancer rotates integrally with the drum, the drum is rotated at such a rotational speed that the centrifugal force acting on the liquid in each storage tank of the balancer becomes larger than the gravity. If so, the liquid in each liquid storage tank is held in the liquid storage tank by centrifugal force, and the eccentric state of the balancer itself is constant. From this state, if the centrifugal force acting on the liquid in the liquid storage tank is reduced to a rotational speed where the centrifugal force falls below the gravity for a short time, the liquid in the liquid storage tank that has just reached the upper rotation during the deceleration Falls through the opening. When the balancer is a closed annular body and liquid is sealed as in the above embodiment, the dropped liquid enters the other storage tank, and the balancer is an open body and the liquid can freely enter and exit In some cases, the dropped liquid is discarded in addition to entering another liquid storage tank. In any case, since the amount of liquid in the liquid storage tank changes, the balancer's eccentricity changes, so the eccentricity change cancels the eccentric load caused by the offset of the laundry and adjusts the balance of the entire drum. be able to.

  Of course, when the drum is decelerated to drop the balancer liquid, the centrifugal force acting on the laundry is also reduced. The laundry before dehydration accommodated in the drum sufficiently contains water, and the laundry and the laundry and the inner peripheral surface of the drum adsorb to each other through the water. Therefore, it is harder for the laundry to drop than the liquid because the suction force acts on the laundry during the drum rotation, but if the rotational speed is too low, the laundry also falls. Since the centrifugal force acting on the laundry at this time is proportional to the distance (radius) from the drum rotation axis to the laundry, the centrifugal force becomes smaller in the inner part of the drum, that is, the laundry closer to the drum rotation axis. Easy to fall.

  When the amount of load is small, the laundry is in direct contact with the inner peripheral surface of the drum, or the distance from the drum rotation shaft to the laundry is relatively long even if the laundry is positioned on the inner side of the drum. On the other hand, when the load is large, the laundry is piled up several times, so that the distance from the drum rotation shaft to the laundry located on the innermost side of the drum is relatively short. Therefore, the balance adjustment control means sets the rotation speed for switching from deceleration to acceleration at the time of temporary deceleration when the load is large compared to when the load is small. Since the centrifugal force is proportional to the square of the rotational speed, if the rotational speed at the time of deceleration is relatively high, a decrease in centrifugal force acting on the laundry at a distance close to the drum rotation axis can be suppressed. Things can be made difficult to fall.

  As described above, according to the drum type washing machine according to the present invention, when the eccentric load caused by the laundry is actively eliminated by using the balancer, the state of the laundry is changed. Therefore, the possibility that the eccentric load of the entire drum can be reduced by the balance adjustment using the balancer is increased. As a result, the time required for the start-up of the dehydration can be shortened, and the dehydration time and thus the time required for washing can be shortened.

  In the drum type washing machine according to the present invention, various methods are conceivable as a method for detecting the load of the water-containing laundry before the start of dehydration. Preferably, components such as a weight sensor and a circuit are added. Therefore, it is desirable to be able to cope with only control, that is, only by adding a control program of the microcomputer. Therefore, specifically, for example, the load amount detection means decelerates the drum from a state where the drum is rotated at the first rotation speed at which the centrifugal force acting on the laundry in the drum is greater than the gravity. When this occurs, the time until the rotational speed of the drum decreases to a second rotational speed at which the centrifugal force acting on the laundry in the drum is greater than gravity and smaller than the first rotational speed is measured. It is preferable to obtain the moment amount and detect the load amount in the water-containing state from the inertia moment amount.

  The method of decelerating the drum is to stop energization of the motor that rotates the drum, short-circuit between the motor terminals and apply the brake using the motor's power generation action (back electromotive force), or the motor rotates in reverse. One of the methods of applying a brake by switching the energization so as to perform can be employed. In such deceleration control, the larger the load amount, the larger the moment of inertia. Therefore, with the above configuration, the load amount can be detected with high accuracy simply by adding a control program.

  Hereinafter, a drum type washing machine according to an embodiment of the present invention will be described with reference to the drawings.

  1 is an external perspective view of the drum type washing machine of the present embodiment, FIG. 2 is a right side vertical sectional view of the main part of the drum type washing machine, and FIG. 3 is a front vertical sectional view of the main part of the drum type washing machine. It is.

  The outer box 1 that forms the outer shape is formed in a curved shape that hangs forward from the upper surface to the front surface, and a large laundry input port 2 is formed in this portion. The upper lid 3 for opening and closing the laundry input port 2 has a structure in which a plurality of strip-shaped slats are connected, and is slidable in the front-rear direction. The upper lid 3 is closed on the right side with the upper lid 3 closed. When the user presses the provided lid opening button 9, the upper lid 3 automatically slides backward as shown by the arrow in FIG. When closing the opened upper lid 3, the user puts his / her finger on the handle 4 provided on the upper front side of the upper lid 3 and pulls it forward. When the upper lid 3 reaches a position at which the laundry input port 2 is completely closed, the upper lid 3 is latched by a latch mechanism (not shown) to keep the closed state.

  Arranged on the right side of the upper lid 3 is an operation panel 5 extending in the front-rear direction and provided with a plurality of operation keys and a display. Note that some of the operation keys that are relatively infrequently used are covered with a lid that can stand up on the rear side. Further, a detergent container 6 covered with a laterally openable lid is provided on the left rear side opposite to the operation panel 5 with the upper lid 3 interposed therebetween. Further, a tap water supply port 7 connected to an external water faucet or the like is provided behind the detergent container 6 via a hose, and connected to the inside of a bath tub or the like via another hose behind the operation panel 5. A bath water supply port 8 is provided.

Next, the internal configuration of the drum type washing machine will be schematically described with reference to FIGS.
On the pedestal 10, an outer tub 11 whose peripheral surface is substantially cylindrical and whose both end surfaces are substantially closed is suspended and supported from above the left and right sides with the end surfaces facing the left and right side surfaces of the outer box 1. The two springs (not shown) and the two dampers 13 that support the lower portion of the outer tub 11 in the front-rear direction are held so as to be moderately swingable. Inside the outer tub 11, a drum 14 in which a large number of water passage holes 14a are perforated and whose peripheral surface is substantially cylindrical and whose both end surfaces are substantially closed is rotatable about a horizontal axis C extending in the left-right direction. Is provided. Three baffles 14b are attached to the inner peripheral surface of the drum 14 at intervals of about 120 ° in the circumferential direction.

  The main shaft 15 fixed to the center of the left end surface of the drum 14 is supported by a bearing 18 held by a first bearing case 17 fixed to the left end surface of the outer tub 11. On the other hand, the auxiliary shaft 16 fixed to the center of the right end surface of the drum 14 is supported by a bearing 20 held by a second bearing case 19 fixed to the right end surface of the outer tub 11. The main shaft 15 and the auxiliary shaft 16 form a horizontal axis C that is a rotation shaft of the drum 14.

  A disc-shaped rotor 21b of a drum motor 21 that is an outer rotor type DC motor is fixed to the tip of the main shaft 15 protruding leftward from the left end surface of the outer tub 11, while the first bearing case also serves as a motor base. 17, the stator 21a of the drum motor 21 is fixed, and the stator 21a and the magnet of the rotor 21b face each other. When a drive current is supplied to the stator 21a from a control circuit (not shown), the rotor 21b rotates accordingly, and the drum 14 is rotationally driven through the main shaft 15 at the same rotational speed as the rotor 21b.

  An outer tub opening 11a is formed at a position coinciding with the laundry input port 2 of the outer box 1 from the upper part of the peripheral surface of the outer tub 11 to the diagonal front, and horizontally in order to open and close the outer tub opening 11a. An inner lid 23 is provided that can stand up rearward about the extending inner lid shaft 22. A drum opening 14c is also formed on the peripheral surface of the drum 14, and a drum cover 25 including two lid bodies 25a and 25b having a double door structure is provided in front and rear in order to open and close the drum opening 14c. . Since the drum 14 is rotatable, it is necessary to stop and maintain the drum 14 at a position where the drum opening 14c and the outer tub opening 11a coincide with each other in the radial direction when the drum lid 25 is opened and closed. In order to fix the position of the drum 14, a drum lock device 26 is provided on the left end surface of the outer tub 11 and below the stator 21a. In the drum lock device 26, the engaging pin 26b is moved up and down by the operation of the built-in torque motor 26a, and the advanced engaging pin 26b is formed at a predetermined rotational position of the rotor 21b. By engaging with the recess 21c, the drum 14 is locked so as not to rotate.

  Furthermore, the outer periphery of each end face of the drum 14 is annular and hollow so as to suppress the vibration of the drum 14 due to the eccentric load caused by the deviation of the laundry when the drum 14 is rotated at high speed during dehydration. A balancer including a balance chamber 27 which is a body is attached. The vibration suppression operation using this balancer will be described later. Although not described in detail here, a heating / blowing device including a fan motor, a drying heater, a water-cooled dehumidifier, and the like is disposed outside the right side surface of the outer tub 11. High-temperature drying air is fed into the air 14, and air containing moisture generated by heat exchange with the wet laundry in the drum 14 is taken out from the outer tub 11, dehumidified and dried, and used in a circulating manner. .

  FIG. 4 is an electric system configuration diagram of a main part of the drum type washing machine of this embodiment. The control unit 30 that functions as a balance adjustment control unit, an eccentricity detection unit, and a load detection unit in the present invention together with a rotation sensor 21d described later is configured around a microcomputer including a CPU, a ROM, a RAM, a timer, and the like. On the basis of the control program stored in the ROM, various controls for performing the operation of each process of washing, rinsing, dehydration and drying are executed.

  The control unit 30 receives a key input signal from an operation unit 5a provided on the operation panel 5 in order for the user to give various settings and instructions, and also detects the water level stored in the outer tub 11. A water level sensor 33, a temperature sensor 34 for detecting the temperature of the water stored in the outer tub 11 or detecting the temperature of the drying air during the drying operation, built in the drum lock device 26, Detection signals are respectively input from the drum lock detection unit 26c for detecting whether the release state.

  An inverter drive unit 32 is connected to the control unit 30, and rotates the drum motor 21 via the inverter drive unit 32 while receiving a signal from a rotation sensor 21 d that generates a pulse signal synchronized with the rotation of the drum motor 21. To control. The rotation sensor 21d is a position sensor using a Hall element, and here, 72 pulse signals per one rotation of the drum motor 21 (that is, one rotation of the drum 14) are generated at equal rotation angle intervals. Therefore, when the drum motor 21 is rotating accurately at a constant speed, pulse signals are generated at equal time intervals, and the control unit 30 detects the rotation speed of the drum motor 21 based on the time intervals of adjacent pulse signals. Can do.

  A load driving unit 31 is connected to the control unit 30, and the fan motor 35 and the drying heater 37 included in the heating / air blowing device and the water supply into the outer tub 11 are controlled via the load driving unit 31. The operation of the water supply valve 38, the drain valve 39 for controlling drainage from the outer tub 11, the torque motor 26a incorporated in the drum lock device 26, and the like are controlled. Furthermore, the control unit 30 sends a display signal to the display unit 5b so as to perform a display corresponding to the operation of the operation unit 5a and a display for notifying the driving progress status.

  Next, a specific configuration of the balancer and its vibration suppression operation will be described with reference to FIG. First, the configuration will be described. The balance chamber 27 is an annular hollow body in which a predetermined amount of liquid (calcium chloride solution or the like) is sealed, and extends in an L shape from the outer peripheral wall surface 271 inside. The partition walls 272 are provided radially at a predetermined angular interval. The partition wall 272 prevents free movement of the liquid sealed inside. Therefore, when the drum 14 is rotated at such a rotational speed that the centrifugal force acting on the liquid sealed in the balance chamber 27 exceeds the weight, the liquid is shifted to the outer peripheral side in each partition chamber 274, and the liquid in the partition chamber 274 Retained. That is, since no liquid moves between the compartments 274, each compartment 274 can be regarded as having a weight added to each position corresponding to the weight of the liquid held therein.

  In this state, when the same amount of liquid is held in all the compartments 274, the eccentric load by the balancer can be regarded as almost zero. On the other hand, when the liquid is held in the specific one or more compartments 274, the balancer unbalances around the rotation axis and an eccentric load exists. In the case where an eccentric load is generated due to a deviation of the laundry that is rotating while being stuck to the inner peripheral surface of the drum 14, the eccentric load of the balancer is intended to be balanced with the eccentric load caused by the laundry. If generated, the eccentric load of the entire drum 14 is reduced. If the position of the eccentric load generated by the balancer and the amount of eccentricity are appropriately controlled, the amount of eccentricity of the entire drum 14 can be reduced to a level that causes no problem from the viewpoint of vibration.

  The execution procedure of balance adjustment using a balancer is as follows. First, at the start of the balance adjustment operation, the drum 14 is rotated at a rotational speed (about 65 to 75 rpm in the case of this drum type washing machine) at which the centrifugal force acting on the liquid in the balance chamber 27 is substantially balanced with gravity. Let At this time, the liquid existing on the outer peripheral side in each partition chamber 274 of the balance chamber 27 sticks by centrifugal force, and the liquid existing on the inner peripheral side of each partition chamber 274 falls by gravity and moves to another partition chamber 274. For this reason, if the drum 14 is rotated for a while at the above rotational speed, the amount of liquid existing in all the compartments 274 can be made substantially the same. In such a state where the liquid amounts are averaged, the eccentric load by the balancer becomes almost zero, and only the eccentric load W due to the deviation of the laundry becomes the eccentric load of the entire drum 14 (FIG. 5A).

  Next, by slightly increasing the rotational speed of the drum 14 (usually about 100 rpm), the centrifugal force applied to the liquid held in each compartment 274 is increased, and the liquid holding state is stabilized. Then, in the state of constant speed control, the eccentric load of the entire drum 14 is detected based on the fluctuation of the rotational speed of the drum 14 (or the rotor 21b), and the drum is detected at a predetermined timing according to the position of the detected eccentric load. The rotational speed of 14 is reduced only for a short time. Then, since the centrifugal force acting on the liquid is reduced, as shown in FIG. 5B, the liquid spills from the compartments 274a, 274b and 274c which are being lifted above the drum 14 and passes below. Enter another compartment.

  Immediately before the deceleration, as shown in FIG. 5 (a), the liquid is relatively easily spilled from the compartment located above the rotation, whereas it rotates past the rotation. In the compartment that is proceeding downward, the projecting portion 273 of the partition wall 272 plays a role of blocking liquid spillage, so that the liquid is hardly spilled. Therefore, when the vehicle is temporarily decelerated as described above, the liquid is spilled from the compartment that is being lifted upward and the compartment that is already located above, but the compartment is proceeding downward in the rotation. The liquid in the room is retained without spilling. That is, since only the liquid contained in the desired compartment falls with high accuracy, by appropriately determining the timing of deceleration, the interior of the compartment near the position where the eccentric load W due to the deviation of the laundry exists is present. The amount of liquid can be reduced and the amount of liquid in the compartment near the position facing it can be increased.

  By repeating the deceleration operation as described above one or more times, finally the liquid in the compartments 274a, 274b, 274c near the position where the eccentric load W exists is almost as shown in FIG. 5C. The amount of liquid increases near the compartment facing it. Thereby, the eccentric load caused by the balancer and the eccentric load caused by the deviation of the laundry are well balanced, and the eccentric load of the entire drum 14 is reduced.

  In the drum type washing machine of the present embodiment, the eccentric load due to the uneven distribution of the laundry can be offset and reduced by the active balance adjustment using the balancer as described above. However, when the laundry is dropped or moved during the balance adjustment as described above and the state of the eccentric load W changes, even if the liquid is moved appropriately, the eccentric load of the entire drum 14 is not reduced. On the other hand, there is a risk of becoming larger. Therefore, in the drum type washing machine of this embodiment, characteristic control is performed at the start of dehydration so as not to cause such a problem.

  Hereinafter, the control operation at the start of dehydration in the initial stage of the dehydration process using the balance adjustment operation will be described in detail with reference to FIGS. 6 and 7 are control flowcharts, and FIG. 8 is a schematic diagram for explaining this control operation. In this washing machine, the intermediate dehydration is performed after the washing operation and the rinsing operation excluding the final rinse, and the final dehydration is performed after the final rinse. The dehydration process here includes both the intermediate dehydration and the final dehydration. .

  When the dehydration process is started, the control unit 30 first operates the drum motor 21 via the inverter drive unit 32 to control the rotation speed of the drum 14 to be increased to 100 rpm (step S10). When the drum 14 is rotated at 100 rpm, the centrifugal force acting on the laundry in the drum 14 becomes larger than gravity, and the laundry is completely attached to the drum 14 in a state where it is stuck to the inner peripheral surface of the drum 14. Rotate.

  When it is detected that the rotation speed has reached 100 rpm based on the pulse signal obtained by the rotation sensor 21d (Yes in step S11), the control unit 30 performs speed control so as to keep the rotation speed at 100 rpm, and the state Then, preliminary eccentricity detection processing is executed (step S12). Here, the amount of eccentricity is obtained based on fluctuations in the actual rotational speed when the constant speed control is performed so as to maintain the rotational speed of the drum 14 at 100 rpm. That is, when an eccentric load is present on the drum 14, when the eccentric load is directed downward from above the drum 14 as the drum 14 rotates, the eccentric load acts to accelerate the drum 14. Acts to decelerate the drum 14 when it goes from below to above the drum 14. Since the rotation speed fluctuates while the drum 14 makes one rotation by the acceleration action and the deceleration action, the control unit 30 obtains the speed fluctuation by measuring the time interval of the pulse signal obtained from the rotation sensor 21d. The amount of eccentricity is estimated according to The amount of eccentricity detected at this time is P1.

  Next, the control unit 30 determines whether or not the eccentric amount P1 is equal to or less than a predetermined threshold value Wa (step S13). The threshold value Wa is a determination value that determines whether or not to perform load amount detection described later. If the eccentric amount P1 exceeds the threshold value Wa, the rotational speed of the drum 14 is reduced or stopped and the loosening operation is executed (step S14), and the process returns to step S10. On the other hand, when the amount of eccentricity P1 is equal to or less than the threshold value Wa, the control unit 30 continuously measures the amount of inertia Q at a rotational speed of 100 rpm, and the amount of laundry in the drum 14 is calculated from the amount of inertia Q. The load amount U is detected (step S15). Specifically, for example, from the state where the drum 14 is rotated at 100 rpm, the energization to the drum motor 21 is temporarily interrupted (or the brake is applied), and the inertial force is based on the pulse signal from the rotation sensor 21d. The time required for the rotational speed of the rotating drum 14 to fall to a predetermined value (for example, 90 rpm) is measured, and the moment of inertia is obtained according to the measurement time. The greater the load, the greater the moment of inertia. The load amount U obtained at this time is a load amount in a state where each laundry sufficiently contains water before dehydration, and is different from the load amount detected before the start of the washing operation, for example, in order to determine a detergent guide amount. It becomes.

  Thereafter, the amount of eccentricity is detected again (step S16), and it is determined whether or not the detected amount of eccentricity P2 is equal to or less than a threshold value Wb that is a balance adjustable range (step S17). Here, the amount of eccentricity is measured in step S16 because it is rare, but the amount of eccentricity may change due to the movement of the laundry when the amount of moment of inertia is determined in step S15. When the eccentric amount P2 exceeds the threshold value Wb, the eccentric amount of the drum 14 is within such a range that the vibration of the outer tub 11 can be allowed during high-speed rotation of the drum even if the balance adjustment using the balancer is performed to the maximum. Can not be reduced. Therefore, the process proceeds to step S14, the rotation of the drum 14 is decelerated to loosen the laundry, and dehydration start-up is retried from the beginning.

  When it is determined in step S17 that the eccentric amount P2 is less than or equal to the threshold value Wb, it is next determined whether or not the same eccentric amount P2 is less than or equal to the threshold value Wc (step S18). The threshold value Wc is a maximum value that falls within a range in which vibration is allowed during high-speed rotation of the drum (usually, a vibration amplitude that does not contact the inner surface of the outer case 1 when the outer tub 11 vibrates is determined as an allowable range). . Therefore, when it is determined that the eccentric amount P2 is equal to or less than the threshold value Wc, the dehydrating operation is started by increasing the rotational speed of the drum 14 to a high speed (about 500 to 1000 rpm) as it is (step S19). Note that the value of the high-speed rotation speed may be set according to, for example, the load amount or the like. Alternatively, the speed is first increased to 500 rpm and the eccentricity is checked again, and the subsequent rotation is performed according to the result. The speed may be determined.

  On the other hand, if it is determined in step S18 that the eccentric amount P2 exceeds the threshold value Wc, if the rotational speed of the drum 14 is increased as it is, that is, without performing balance adjustment, there is a high possibility that abnormal vibration will occur. A balance adjustment operation is executed (step S20), and then the process returns to step S16 to check the eccentricity after the balance adjustment is executed.

  Although the basic operation of the balance adjustment is as described above, the drum type washing machine of the present embodiment executes the above characteristic control. That is, at the time of balance adjustment, first, the rotational speed of the drum 14 is maintained at 100 rpm (step S21). At this time, the centrifugal force acting on the liquid in the balance chamber 27 is greater than the gravity, and the liquid is held in the respective compartments 274 and does not move between the compartments 274. On the other hand, since the centrifugal force acting on the laundry accommodated in the drum 14 is also larger than the weight, the laundry rotates integrally with the drum 14 so as to stick to the inner peripheral surface of the drum 14. In this state, the control unit 30 detects the position of the eccentric load from the fluctuation state of the rotational speed of the drum 14.

  As described above, since the eccentric load is obtained every time the pulse signal from the rotation sensor 21d is obtained, it can be considered that the eccentric load is monitored almost continuously. The controller 30 tracks the position of the eccentric load, and repeatedly determines whether or not the eccentric position has reached a predetermined rotational position (step S22). When it is detected that the eccentric position has reached the predetermined rotational position, the electric brake is activated to rapidly decrease the rotational speed (step S23). When the brake is actuated to rapidly reduce the rotation speed and the centrifugal force acting on the liquid in the balance chamber 27 becomes smaller than the gravity, the liquid is discharged from the compartment 274 located above the rotation of the drum 14 as described above. Falls and moves to the compartment 274 passing underneath.

  The timing for returning the rotational speed of the drum 14 to 100 rpm again after the brake is once actuated to lower the rotational speed of the drum 14 is determined as follows. That is, it is determined whether or not the previously detected load amount U is 5 kg or less (step S24). If the load amount U is 5 kg or less, whether or not the rotational speed after deceleration has reached 58 rpm. Is repeatedly determined (step S25), and when the rotational speed falls to 58 rpm, rapid acceleration is performed with 100 rpm as a target (step S29). If the load amount U exceeds 5 kg in step S24, it is next determined whether or not the load amount U is 15 kg or less (step S26). If the load amount U is 15 kg or less, that is, 5 kg and 15 kg. If it is between, it is repeatedly determined whether or not the rotational speed after deceleration has reached 60 rpm (step S25), and when the rotational speed drops to 60 rpm, rapid acceleration is performed targeting 100 rpm. Further, when the load amount U exceeds 15 kg in step S26, it is repeatedly determined whether or not the rotational speed after deceleration has reached 62 rpm (step S28), and when the rotational speed drops to 62 rpm, 100 rpm is set. Rapid acceleration to the target.

  That is, the rotational speed that determines the timing for switching from deceleration to acceleration is 58 rpm when the load amount U is 5 kg or less, 60 rpm when the load amount U is 5 kg to 15 kg, and 62 rpm when the load amount U is 15 kg or more. The higher rotation speed is set. This is due to the following reason.

  FIGS. 8A and 8B schematically show the state of the laundry in the drum 14 when the drum 14 is rotating at 100 rpm in the case of a small load and a large load, respectively. In the case of a small load, since there is little laundry, each laundry sticks directly to the inner peripheral surface of the drum 14 and rotates integrally with the drum 14. On the other hand, in the case of a heavy load, since there are many laundry items, the laundry items overlap each other and stick to the inner peripheral surface of the drum 14 as a whole and rotate integrally with the drum 14. Considering the laundry present at a position close to the drum rotation axis, when the load is small, the radius r1 to the laundry is almost the same as the radius of the drum 14 because it sticks to the inner peripheral surface of the drum 14. long. On the other hand, in the case of a heavy load, the laundry on the innermost periphery of the stacked laundry is closest to the drum rotation shaft, and the radius r2 from the drum rotation shaft to the laundry is considerably shorter than r1.

  Since the centrifugal force acting on the laundry is proportional to this radius and proportional to the square of the rotational speed, even if the rotational speed is such that the laundry does not fall under a small load, the laundry on the inner circumference side will It will fall. Therefore, it is necessary to increase the rotation speed in order to prevent the laundry from falling even in the case of a large load so that the eccentric load caused by the side of the laundry does not change. However, since the centrifugal force is proportional to the square of the rotational speed as described above, the rotational speed need not be changed as much as the difference in radius.

  In this way, by setting the rotation speed at the time of deceleration higher than in the case of a small amount of load in the case of a large amount of load, the laundry that is close to the drum rotation axis and easily falls can fall during the balance adjustment operation. It is possible to prevent the eccentric load itself due to the deviation of the laundry from changing. Even if the rotational speed at the time of reversal from deceleration to acceleration changes in the range of 58 to 62 rpm, the centrifugal force acting on the liquid held in the compartment 274 of the balance chamber 27 becomes smaller than gravity. Since there is no change, there is almost no influence on the movement operation of the liquid in the balance chamber 27. Therefore, the probability that the eccentric load resulting from the deviation of the laundry can be reduced by the balance adjustment is improved.

  The above-described embodiment is an example of the present invention, and it is obvious that changes, modifications, or additions can be made as appropriate within the scope of the present invention. For example, in the above embodiment, the balance is adjusted by moving the liquid sealed in the balance chamber, which is a sealed annular body. For example, the openings on the inner peripheral side of a plurality of liquid storage tanks corresponding to the compartments are outside. Filled with a liquid such as water into a liquid storage tank that is provided so as to open in the tank and rotates integrally with the drum by a separately provided water injection mechanism, and by decelerating the drum, It is good also as a structure which performs balance adjustment by discarding a liquid.

1 is an external perspective view of a drum type washing machine according to an embodiment of the present invention. The right side longitudinal cross-sectional view of the principal part of the drum type washing machine by a present Example. The front longitudinal cross-sectional view of the principal part of the drum type washing machine by a present Example. The electric system block diagram of the principal part of the drum type washing machine by a present Example. The schematic explanatory drawing of the vibration suppression operation | movement using the balancer in the drum type washing machine by a present Example. The flowchart which shows the control action at the time of starting of spin-drying | dehydration in the drum type washing machine by a present Example. The flowchart which shows the control action at the time of starting of spin-drying | dehydration in the drum type washing machine by a present Example. The schematic diagram for demonstrating the control action at the time of starting of spin-drying | dehydration in the drum type washing machine by a present Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer box 11 ... Outer tank 14 ... Drum 15 ... Main shaft 16 ... Auxiliary shaft 21 ... Drum motor 21d ... Rotation sensor 30 ... Control part 32 ... Inverter drive part

Claims (3)

In a drum-type washing machine for dehydrating the laundry by rotating the drum containing the laundry at high speed around a horizontal axis or an inclined axis,
A load amount detecting means for detecting a load amount in a wet state before the start of dehydration;
In order to generate a load on the drum that counteracts the eccentric load caused by the deviation of the laundry in the drum, the drum is mounted on one or both end surfaces of the drum and formed radially around the drum rotation axis. A balancer having a plurality of liquid storage tanks having openings on the inner peripheral side;
While the drum is rotating at a rotational speed at which the centrifugal force acting on the laundry in the drum is greater than gravity and lower than the resonant rotational speed corresponding to the resonance point, An eccentric load detecting means for detecting an eccentric load caused by the offset, and
From the state where the drum is rotated at such a rotational speed that the centrifugal force acting on the liquid in each liquid storage tank of the balancer is greater than the gravity, the rotational position of the eccentric load detected by the eccentric load detecting means is changed. By decelerating for a short time at the appropriate timing, the liquid in the liquid storage tank located above the rotation is dropped and moved to another liquid storage tank or discarded, thereby changing the eccentric state of the balancer. Balance adjustment control means for adjusting the balance of the entire drum, and a balance adjustment control means for changing the rotational speed for switching from deceleration to acceleration during deceleration according to the load amount by the load amount detection means,
A drum-type washing machine comprising: The balancer includes a sealed annular body that is concentrically and integrally rotatable with the drum and has a hollow inside, and a liquid sealed in the annular body, and an outer periphery of the sealed annular body A plurality of partition walls project radially inward from the surface side, and communicate with each other on the inner peripheral surface side between adjacent partition walls, and a plurality of compartments capable of holding the liquid on the outer peripheral surface side by centrifugal force. Having as said liquid storage tank,
The balance adjustment control means temporarily lowers the rotational speed of the drum and balancer from a state where the centrifugal force acting on the liquid held in the compartment rotates at a rotational speed that overcomes gravity, The drum type washing machine according to claim 1, wherein the liquid held in each compartment is moved to another compartment.   The load amount detection means is configured to decelerate the drum from a state where the drum is rotated at a first rotation speed at which the centrifugal force acting on the laundry in the drum is greater than gravity. The time until the rotational speed of the drum decreases to a second rotational speed at which the centrifugal force acting on the laundry is greater than gravity and smaller than the first rotational speed is measured, and the moment of inertia is obtained from the measured time. The drum type washing machine according to claim 1 or 2, wherein a load amount in a water-containing state is detected from a moment amount.

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